Optical coherence tomography (OCT) is an imaging modality that provides a micron-level look at the tissues being examined. It is used in ophthalmology to assess the eyes and for imaging the interior of arteries to help with atherectomies. Although OCT has significant potential to help clinicians evaluate the health of tissues, it has proven difficult to use deep within the body.
Now, researchers at Duke University have managed to equip a rigid borescope, the kind used to look inside joints during arthroscopies, with OCT imaging capability. The borescope, with a diameter of only 4 mm, was used to assess the state of cartilage within the knees of lab pigs.
“We saw a need for OCT image guidance in arthroscopic surgery, a minimally invasive procedure that uses an endoscope to address joint damage,” said Evan T. Jelly, the research lead in a press release. “We took the low-cost OCT imaging platform we previously developed and adapted it to meet the requirements of this application.”
The new device works by channeling the imaging data from the tissue to the fiber optic component located in the back of the scope. The narrow front allows the device to enter narrow cavities while the larger components are located further back. This approach allowed the team to avoid enlarging the scope, keeping it small enough to be applicable in procedures currently performed on a routine basis.
Using the scope, the researchers were able to measure the thickness of the cartilage in the pigs, without having to create an incision in the target tissues. The same will hopefully be possible in humans, although that remains to be seen since human cartilage tends to be thicker compared with the porcine kind.
If OCT finally does become a common modality for imaging the interior of the body, it may help to better direct the treatment of a variety of orthopedic and other conditions. “By developing a new portable, low-cost version of OCT, we show that the success of this imaging approach will no longer be limited to ophthalmology applications,” said Jelly. “With some engineering expertise, this OCT platform can be adapted to fit a wide range of clinical needs.”